An erection aid of the general type to which the present invention relates is shown in German Patentschrift No. 427,488. The device shown therein involves an inflatable elastic ring which encompasses the penis and which, when inflated by means of the valve provided for this purpose, is intended to subject the penis to ring compression. The effect of this is to block the flow of venous returning blood while permitting continued arterial flow into the penis. The corpora cavernosa thus fill and the desired erection is achieved. An erection aid of this type can be used to treat impotence of any kind whether due to psychological or physiological causes.
An advantage of this familiar construction is that the erection aid is in the form of a soft, elastic tube so that any risk of injury is avoided. Neither the penis nor the partner can be injured. No kind of injury can result from the bumping of the soft elastic tube against the female genital region.
This known construction is made with a uniformly constructed annular tube. This tubular ring, in accordance with its purpose, is intended to expand to some extent inwardly in order to achieve the desired compression effect. Resistance is created from within by the penis, however, which opposes the inward expansion of the ring. Thus, the known tube is forced to expand predominantly to the side, that is, in the direction of the longitudinal axis of the penis which is essentially the same as the central axis of symmetry of the ring. The result, therefore, is a substantial increase in the dimension of the ring in the direction of the length of the penis. This is disadvantageous because it diminishes the available length of penis which is essential for success in accordance with the purpose and threatens the success itself if the corresponding physical constitution of the patient is also a factor, particularly in the case of obesity in conjunction with below average penis length.
It is known to use a tube having uniform wall thickness but this does not work well because the tube expands primarily outwardly, not inwardly. In order to overcome this difficulty, efforts to confine the ring have been tried such as shown in U.S. Pat. No. 3,820,533, Jones, in which the confining structure constitutes a hard outer shell containing a ring of uniform wall thickness. However, this does not work either. If the rigid ring is formed so that its inner diameter equals the outer diameter of the flaccid penis, then when the elastic ring is inflated to cause erection, the penis expands radially and is strangulated by the inelastic confining structure. This is a dramatic, painful and dangerous situation. On the other hand, if the rigid ring is made with an inner diameter significantly larger than the flaccid penis, then the expanding tube has free, unconfined areas to the side (axially) in which areas the tube can expand in an uncontrolled fashion, forming bubbles wherever a slight thinning of the tube wall occurs. A similar result is obtained with structures such as shown in U.S. Pat. No. 4,417,567, Trick.